I've been playing a little bit with sphinx2
(http://www.speech.cs.cmu.edu/speech/sphinx/index.html) and it might hit
the bill.
It's BSD style licensed, and works in real time. As a test I made a set
of config files with basic UT things (like "Bravo attack" and "Charlie
cover me") and it works pretty well at least in my command line tests.
They include a sample TCP based server implementation in the code which
might be a place to start.
I'm enjoying the hell out of the game so this is certainly not a deal
breaker, but it certainly would be cool.
Thanks
-Scott